TABLE 2.

Hemagglutination of erythrocytes from different species by SV and human parainfluenza viruses^a

Virus	Strain	Hemagglutination titer for erythrocytes from:
		Guinea pig	Human	Cow	Horse
hPIV-1	C35	512	128	128	<2
hPIV-3	C243	512	128	128	<2
SV	Enders	512	512	512	256

^aEach virus was diluted serially with PBS in a microtiter plate, and then a 0.5% (vol/vol) suspension of erythrocytes was added to each well as described in Materials and Methods. The hemagglutination titer was defined as the maximum dilution of virus that caused hemagglutination.